Electric toothbrush

ABSTRACT

A MOTOR-DRIVEN TOOTHBRUSH IS PROVIDED WHEREIN THE BRUSH IS ROTATED CONTINUOUSLY IN EITHER DIRECTION BY MEANS OF A REVERSIBLE MOTOR MOUNTED IN THE HANDLE. THE BRUSH AND STEM ARE DETACHABLY CONNECTED TO THE MOTOR DRIVE ROD AND BOTH THE STEM AND THE BRUSH ARE ENCLOSED WITHIN A SLEEVE ATTACHED TO A MOTOR HOUSING. THE END OF THE SLEEVE ENCLOSING THE BRUSH IS FORMED WITH A HOODED OPENING TO EXPOSE ONLY AN ANGULAR SECTION OF THE BRUSH. THE SLEEVE IS IN TWO LONGITUDINAL PARTS HINGED TOGETHER TO PERMIT READY REPLACEMENT OF THE BRUSH AND EASE OF CLEANING.

Jan; 5, 1971 5 GRQSSMAN 3,551,932

ELECTRIC TOOTHBRUSH Filed Feb. 20, 1969 INVENTOR. SIDNEY GROSSMAN ATTORNEYS United States Patent 3,551,932 ELECTRIC TOOTHBRUSH Sidney Grossman, 180 Samoset Ave., Quincy, Mass. 02138 Filed Feb. 20, 1969, Ser. No. 800,921 Int. Cl. A46f 13/02 U.S. Cl. --23 9 Claims ABSTRACT OF THE DISCLOSURE A motor-driven toothbrush is provided wherein the brush is rotated continuously in either direction by means of a reversible motor mounted in the handle. The brush and stem are detachably connected to the motor drive rod and both the stem and the brush are enclosed within a sleeve attached to a motor housing. The end of the sleeve enclosing the brush is formed with a hooded opening to expose only an angular section of the brush. The sleeve is in two longitudinal parts hinged together to permit ready replacement of the brush and ease of cleaning.

BACKGROUND OF THE INVENTION (1) Field of the invention This invention relates generally to electric toothbrushes and more particularly is directed towards an electric toothbrush having replaceable brush and brush sleeve components.

(2) History of the prior art Most electric toothbrushes currently available employ an oscillating brush on the end of a motor-driven stem with the brush oscillating through an angle of 45 to 90. Such motor-driven brushes while effective in cleaning the teeth tend to have an ill effect on the gums insofar as small particles of food, for example, which may be lodged between adjacent teeth or between the teeth and the gum tend to be driven up under the gum and may be a source of subsequent irritation or more serious gum ailments. Also, electric toothbrushes heretofore available employ brushes and sleeves for brushes which are not readily removable or replaceable which is desirable where several members of a family, for example, may be using the same motor unit and each member is furnished with his own brush and sleeve.

Accordingly it is an object of the present invention to provide improvements in electric toothbrushes and more particularly to provide an electric toothbrush having a brush with an elongated stem and a sleeve enclosing the stem and a portion of the brush, both of which may be separated quickly and easily from the motor housing for cleaning and replacement.

SUMMARY OF THE INVENTION This invention features an electric toothbrush comprising an electrically reversible motor mounted in a handle housing and drivingly connected to the stem of a rotary brush. The stem and its brush are enclosed by means of a sleeve that is separable from the housing and the sleeve is formed into longitudinal sections hinged to one another permitting quick and easy replacement of the brush and stem.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view in side elevation, partly in section, of an electric toothbrush made according to the invention,

FIG. 2 is a cross-sectional view taken along the line 22 of FIG. 1,

FIG. 3 is a cross-sectional view taken along the line 33 of FIG. 1,

FIG. 4 is a view in perspective of the sleeve shown in open position,

3,551,932 Patented Jan. 5, 1971 ice ing a modification of the connecting arrangement between the sleeve and housing, and,

FIG. 7 is a side elevation of another modification.

DETAIL DESCRIPTION OF THE PREFERRED EMODIMENTS Referring now to the drawings, there is shown in FIG. 1 an electric toothbrush generally indicated by reference character 10 comprised of a handle portion 12 housing an electrically reversible motor 14 operated by means of a switch 16. The motor 14 may be operated by means of a cord plugged into a regular electrical outlet, by batteries or by a rechargeable cell, as desired.

The motor 14 is provided with a drive rod 18 adapted to connect detachably with a stem 20 for a rotary brush 22 as by means of a spline connection 24. The brush head 22 preferably has a cylindrical configuration the bristles being arranged in a helix about the tip of the stem 20.

The brush and stem are supported and substantially enclosed by means of a tubular sleeve 26. The sleeve 26 serves to enclose the shank of the stem 20 to prevent contact between the rotating stem and the inside of the mouth when using the brush and also to support the elongated stem. The sleeve also serves to enclose an arcuate section of the brush so that only a portion of the brush is exposed for contact with the teeth thus protecting the inside of the cheek during the brushing operation.

The tubular sleeve 26, as best shown in FIG. 4, is comprised of a shank portion 28 and a hooded portion 30. The shank portion is cylindrical and formed in two longitudinal semi-cylindrical sections 32 and 34 hinged to one another as by hinge joints 36. One or more hasps 38 are provided for locking the two halves together in closed position. The shank portion of the sleeve is also provided with internal annular ribs 40 spaced along the length of the shank portion to serve as bearing supports for the brush stem 20 and engage annular stem grooves 41 to axially position the stem. Preferably the ribs 40 are narrow to provide low frictional contact support for the stem.

The hooded portion 30 of the sleeve is slightly larger in diameter than the shank portion and is provided with an open section 42 through which an arcuate sector of the brush 22 is exposed for brushing action, the remaining portion of the brush being enclosed by the hood 30. The hood portion is provided with a semi-circular end wall 44 which not only encloses the outer end of the brush but also serves as an end-bearing support for the stem. As best shown in FIG. 1, the wall 44 is formed with an internal socket 46 which receives the tip end of the stem 20 whereby the brush stem is fully supported throughout its length and only a portion of the moving brush is exposed for brushing action all other portions of the mechanism being enclosed.

The right-hand end of the sleeve is formed with a detent 48 adapted to snap into engagement with a cooperating indent 50 formed in a recess at the end of the handle housing 12 which receives the sleeve. The sleeve typically is fabricated from plastic or the like and has sufficient resiliency that the sleeve may be snapped into position in the end of the handle and may be quickly removed by a squeezing pulling action. Once the sleeve is separated from the handle, the brush may be removed for cleaning or replaced by simply opening the hasp to permit the sleeve halves to be opened as shown in FIG. 4. A new brush may be quickly and easily inserted by simply placing the tip in the socket 46 and stem within the shank of the sleeve. The sleeve is then closed, locked and inserted back into the handle.

Referring now to FIG. 6 there is shown a modification of the invention and in this embodiment a sleeve 26', otherwise similar to the sleeve 26 in FIG. 1, is provided with a resilient finger 52 which extends from the shank of the sleeve from a point near the right-hand end thereof in generally spaced parallel relation for engaging a cooperating recess 54 in the end of the handle. The finger 52 is provided with a detent or catch 56 engageable with a cooperating indent in the recess 54. The recess 54 has sufficient clearance to permit the finger to be depressed during an insertion and removal operation. It will be uderstood that the lock provided by the finger 52 permits separation of the sleeve from the handle by merely depressing the finger to release the catch.

Referring now to FIG. 7 there is shown another modification of the invention and in this embodiment the walls of the sleeve are perforated to facilitate draining and rinsing.

The brush being fully rotatable and reversible provides optimum cleaning action regardless which side of the mouth is being brushed since the direction may be selectively reversed for optimum cleaning action. In practice, it is desired that the brush rotate away rather than into the gums. The sleeve not only encloses all moving parts except the exposed section of the brush but also supports it and permits quick and easy replacement and cleaning.

Having thus described the invention what I claim and desire to obtain by Letters Patent of the United States 1. A power driven toothbrush, comprising (a) a housing,

(b) a motor mounted in said housing,

(c) an elongated stern detachably connected to said motor and extending outwardly of said housing,

(d) a brush mounted to the outer end of said stem,

and,

(e) a tubular sleeve detachably connected to said 4 housing and enclosing said stem and a portion of said brush,

(f) said sleeve being formed in a plurality of longi tudinal sections detachably locked together whereby said sleeve may be opened and closed for removal of said stem and brush.

2. A power driven toothbrush according to claim 1 wherein said motor is reversible.

3. A power driven toothbrush according to claim 1 wherein said sleeve is in two semi-cylindrical sections hinged to one another and lockable in a closed position.

4. A power driven toothbrush according to claim 1 wherein said sleeve in formed with a plurality of spaced internal annular ribs engaging said stem.

5. A power driven toothbrush according to claim 4 wherein said stem is formed with a plurality of spaced annular grooves engaging said ribs.

6. A power driven toothbrush according to claim 1 wherein said sleeve is formed with a hooded portion enclosing a portion of said brush, said hooded portion being formed with a socket adapted to receive the outer end of said stem.

7. A power driven toothbrush according to claim 1 wherein said housing and said sleeve are formed with cooperating indents and detents for locking engagement.

8. A power driven toothbrush according to claim 1 wherein said housing is formed with a socket and said sleeve is formed with a resilient finger insertable therein for locking engagement therewith.

9. A power driven toothbrush according to claim 1 wherein said sleeve is perforated.

References Cited UNITED STATES PATENTS 3,430,279 3/1969 Hintze 1523 EDWARD L. ROBERTS, Primary Examiner 

